Gephardt, the former House Democratic leader, resurrected Dean's 1990s comments on overhauling the Medicare program and increasing the Social Security retirement age to link him to Gingrich and the GOP policies of the "Contract With America." The critique reflected Gephardt's determination to cut Dean's advantage in Iowa as well as energize his own campaign.

"It was in this period when Gingrich said Republicans wouldn't immediately kill Medicare. Instead, they would let it wither on the vine," Gephardt said. "And it was also during this time that Howard Dean, as chairman of the National Governors Association, was supporting Republican efforts to scale back Medicare."

Several of the Democratic candidates have stepped up their attacks on Dean in recent days, whether assailing his comments on Israel and race, or taking issue with his call to repeal all of President Bush's tax cuts. Gephardt's comments were his strongest to date against the former Vermont governor, or any other primary foe.

The Dean campaign, in a statement, fired back.

"It is a sad day for Dick Gephardt when he compares any Democratic candidate running for president to Newt Gingrich and his divisive policies. No Democrat in the presidential race bears any resemblance to Newt Gingrich on any major issue. And for Dick Gephardt to suggest otherwise is simply beyond the pale."

Lieberman to back D.C. school vouchers

WASHINGTON - Sen. Joe Lieberman said Friday he will vote in favor of a hotly contested plan to provide private school vouchers to low-income students in the nation's capital.

The Senate vote, which could come next week, may further erode his support among union members, who booed him during the AFL-CIO's presidential forum last month for backing vouchers.

"We're not surprised, although surely we're disappointed," said National Education Association spokeswoman Kathleen Lyons. "His vote on this is going to have an impact on his campaign."

The 2.7-million-member union has yet to endorse a Democratic candidate for president. Lyons said the group doesn't have a litmus test, but "this certainly would cause us a lot of concern. It's a very important issue for public education."

The measure would provide $13-million so that thousands of low-income students could go to private schools and receive up to $7,500 to defray the costs. A similar bill passed in the House by one vote, but other Democratic senators are vowing to defeat the bill in the Senate.

Lieberman, D-Conn., said he doesn't want to close the door on any idea that will help students "stuck in bad schools."

"This proposal mirrors the voucher bills I have supported before," he said. "It targets low-income students, does not take away funding from the public schools and includes a strong evaluation component to see if this approach works."